| commit | 202a3b831d7b85d9edde37c6ec579dea7b4d7dfe | [log] [tgz] |
|---|---|---|
| author | James Farrell <[email protected]> | Mon Aug 26 20:42:39 2024 +0000 |
| committer | James Farrell <[email protected]> | Mon Aug 26 20:42:39 2024 +0000 |
| tree | 8afd75c4127a9e54114998727b70871d7ebda491 | |
| parent | d9b73408989e29efe89f4ae4cb64833022179b91 [diff] |
Migrate 25 crates to monorepo. combine command-fds const-oid coset crc32fast criterion criterion-plot crossbeam-channel crossbeam-deque crossbeam-epoch crossbeam-queue crossbeam-utils darling_core darling_macro dashmap data-encoding der der_derive derive_arbitrary displaydoc document-features downcast-rs drm either enumn Bug: 339424309 Test: treehugger Change-Id: Ifbf4afbd6d6628f35b83f4b720079a5ec7fa8027
A safe interface to the Direct Rendering Manager.
The Direct Rendering Manager is a subsystem found on multiple Unix-based operating systems that provides a userspace API to graphics hardware. See the Wikipedia article for more details.
The DRM is accessed using ioctls on a file representing a graphics card. These can normally be found in /dev/dri, but can also be opened in other ways (ex. udev).
This crate does not provide a method of opening these files. Instead, the user program must provide a way to access the file descriptor representing the device through the AsFd trait. Here is a basic example using File as a backend:
/// A simple wrapper for a device node. pub struct Card(std::fs::File); /// Implementing [`AsFd`] is a prerequisite to implementing the traits found /// in this crate. Here, we are just calling [`File::as_fd()`] on the inner /// [`File`]. impl AsFd for Card { fn as_fd(&self) -> BorrowedFd<'_> { self.0.as_fd() } } /// Simple helper methods for opening a `Card`. impl Card { pub fn open(path: &str) -> Self { let mut options = std::fs::OpenOptions::new(); options.read(true); options.write(true); Card(options.open(path).unwrap()) } }
Finally, you can implement drm::Device to gain access to the basic DRM functionality:
impl drm::Device for Card {} fn main() { let gpu = Card::open("/dev/dri/card0"); println!("{:#?}", gpu.get_driver().unwrap()); }
See drm::control::Device as well as our mode-setting examples: atomic_modeset and legacy_modeset
Rendering is done by creating and attaching framebuffers to crtcs.
A framebuffer is created from anything implementing Buffer like the always available, but very limited, DumbBuffer.
For faster hardware-backed buffers, checkout gbm.rs.